Šiljastokutni trokut
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kome su
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,
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i
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polovišta stranica
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,
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i
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upisan je u kružnicu sa središtem u točki
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polumjera
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. Dokažite da je
%V0
Šiljastokutni trokut $ABC$ kome su $A_1$, $B_1$ i $C_1$ polovišta stranica $\overline{BC}$, $\overline{CA}$ i $\overline{AB}$ upisan je u kružnicu sa središtem u točki $O$ polumjera $1$. Dokažite da je
$$\frac{1}{|OA_1|}+\frac{1}{|OB_1|}+\frac{1}{|OC_1|} \geq 6$$